Dengler wrote in a brief statement Microsoft recognizes vector graphics are an important component of the "next-generation web platform", and the company's decision to join is evidence of its commitment to participating in the standards process around that.

Reaction was swift and overwhelming. Commentors responding to Dengler's post overwhelmingly welcomed Microsoft's move, with people hoping it'll lead to SVG support in IE 9.

This from a commenter called "modgen" was typical: "Great news if this leads to SVG support in IE sometime in the not too distant future. Long overdue, in my opinion."

But there's many a slip between participation and implementation, and commenters are right to temper their enthusiasm and not assume simply joining the working group will mean support for SVG in IE. There have been complaints of Microsoft joining industry technology working groups in years past without it actually actively participating.

SVG is part of the magnum opus that is the still unfinished HTML 5 that provides a language for describing two-dimensional graphics and graphical applications in XML.

It's already widely supported, in Firefox, Chrome and Opera - the former two of which have been steadily eating up market share against IE.

Microsoft has certainly been making the right noises in terms of support for SVG, as part of a broader commitment embrace standards in its browser.

But when Microsoft speaks, it's stopped short of committing specifically to SVG. Instead, it's either hedged by talking about the difficulty in fully supporting the list of technologies in HTML 5 or it's talked in terms of supporting "real world" specs, those that actually get used, as opposed - we presume - to vanity or feel-good specs.

However, some specs are more important that others on the W3C's shopping list, and SVG is near the top of the list for many developers based on its support by Mozilla, Google, and Opera Software along with the community in general.

Being charitable to Microsoft, it sounds as if the reason Microsoft is being slow is because it's decided to saddle itself with the work of building comprehensive test suites to ensure whatever specification it implements actually works properly. Microsoft submitted 3,784 test suites for CSS 2.1 in IE 8 to the W3C in January 2009.

Asked by The Reg last spring whether IE 9 would support SVG, IE general manager Dean Hachamovitch reinforced the comprehensive-test-suites message. "I think it's important to not just do SVG but have complete tests so SVG works the way developers want it to," he said.

Practicalities aside, there's the challenge of Microsoft's own politics that SVG must overcome, and Microsoft knowing what its plans are for graphics in the browser.

Microsoft has long gone its own way on many things. In browser-based graphics, IE went with Vector Markup Language during the 1990s and most of the 2000s. This was devised by Microsoft and others and rejected by the W3C as a potential standard. Latterly, it has gone with XAML.

Now, though, the focus is on Windows Presentation Foundation (WPF) for graphics and specifically Silverlight. Currently, Silverlight is a lightweight subset of WPF but the debate, we've heard, inside Microsoft is how far to add new features and make Silverlight the graphics layer for Windows.

Certainly Silverlight, Microsoft's rising star, can easily handle the kind of 2D graphics work tackle by SVG, and is being pitched not just for video and audio but more bread-and-butter graphics that involve characters or charts. The question is, how far Microsoft takes Silverlight and whether Silverlight becomes Microsoft's chosen graphics platform.

The final challenge for SVG will come if it's implemented by Microsoft in IE. The company must resist what's in its DNA: to tweak - or "optimize" - the specification for "improved performance" or a "richer" experience as it's done elsewhere. Failure on this front will simply mean a repeat of the problems developers currently face in working with different browsers.

On rendering of graphics, at least, Microsoft is already talking optimization of its rendering engine to take advantage of a PC's underlying hardware, even though IE 9 will run CSS and HTML. Microsoft is away from its Graphics Device Interface (GDI) to its DirectX, pioneered by Microsoft for use in games but adopted widely in Windows 7.

The president of Microsoft's Windows and Windows Live division Steven Sinofsky explained the belief in manifest optimization at Microsoft's Professional Developers' Conference (PDC) last November. "We think that the hardware that you run on should shine through in the browser, even when just using standards-based rendering," he said.

Microsoft's decision to join the W3C's SVG working group is certainly a step in the right direction, and Microsoft's rhetoric of support for standards in IE does sound promising.

The question is whether SVG becomes Microsoft's next front in IE's standards support, meaning it actually commits resources to the task. And that will depend on the larger strategic question of whether Microsoft decides to make Silverlight its graphics flagship, or Silverlight becomes a player in a larger cast of options Microsoft offers developers on graphics. ®